Question

Which of the following reactions of glucose can be explained only by its cyclic structure?
(a) Glucose forms pentaacetate
(b) Blucose reacts with hydoxylamine to form an oxime
(c) Pentaacetate of glucose does not reach with hydroxyl amine
(d) Glucose is oxidised by nitric acid to gluconic acid

Answer 1

(c) "Pentaacetate of glucose does not react with hydroxylamine" showing the absence of free -CHO group. This can not be explained by open structure of glucose. While all other properties are easily explained by open structure of glucose.
Hence, Option (c) is the correct choice.